Smart Data Solutions Entry Level Software Engineer interview questions

After a phone interview I came in for a test of my java skills. I rang the doorbell and waited a while before someone came to the door, and then I had to wait some time longer to start my "test". I was taken to a secluded computer and they returned only when I was done. They said they'd contact me in a week, but would not respond to my emails. Very unprofessional and I think it's a scam for free labor on minor tasks.

I applied through Indeed and a few weeks later got an email asking me to come take a technical exam, this was not an interview. They told me to ring the doorbell, so I did and someone took me to a desk with a laptop and mouse in a dark corner of the office which was pretty much empty. The laptop had eclipse open with a project started and some interfaces you must implement to convert a fixed column .dat file into a comma separated value .csv file. It wasn't very difficult but if you haven't actually implement something like that before then the hour might be tight.